The following discussion refers in the first instance to the example of dental implants. For taking an impression of the situation in the patient's mouth and for transferring the impression obtained to a master cast, on which the tooth replacement is then modeled, a number of elements have hitherto been used. The work steps that have had to be performed, and the elements used in these work steps, are dealt with in detail by SCHROEDER, A.; SUTTER, F.; BUSER, D.; KREKELER, G.: Orale Implantologie [Oral implantology], Georg Thieme Verlag Stuttgart, 2nd edition, 1994, page 202 et seq. On the one hand, the assembling of the elements in the patient's mouth, particularly in the area of the molars, is problematic because of the resulting overall height of the elements, especially if a screwing instrument has to be used as well. Moreover, the work procedures are demanding for the patient, and they are time-consuming as regards impression-taking and production of the master cast. In addition to this, inaccuracies occur. The difficulties result primarily from the fact that the impression cap does not hold itself on the implant fitted in the mouth or on the manipulation implant to be used subsequently in the production of the master cast. DE 44 15 670 A1 discloses an impression cap which, at the open end facing the implant, has resilient flaps which, when applied, engage over the shoulder of the conical superstructure, the latter being fitted into the implant. The impression cap described there cannot therefore be used for taking an impression of the implant end protruding from the gingiva and projecting into the mouth, but instead only for taking an impression of the outer contour of the superstructure while the implant is positioned below the gingiva.
U.S. Pat. No. 6,068,478 discloses alternatives to the prior impression/implant systems. U.S. Pat. No. 6,068,478 describes an impression system which comprises as its principal component an impression cap for transferring an end, protruding from a human tissue structure, of an implant which is fitted in the human body, including possible superstructures, to a master cast. The outwardly directed implant end has an undercut contour on its outside, and the impression cap has a geometry which complements the undercut contour and engages therein. The undercut contour is formed either by an implant geometry tapering in a trumpet shape towards the implant bed, or by a recess near the implant end. After the impression cap is secured to the implant, it is encased in impression material. The impression cap embedded in the impression compound present in the impression tray is removed from the fitted implant and receives a manipulation implant to make a master cast.
The present invention addresses further constructive alternatives to the prior impression/implant systems.
All U.S. patents and applications all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention in any way, the invention is briefly summarized in some of its aspects below.